The present invention is directed, in general, to heat transfer and, more specifically, to a system for extracting heat from electrical devices on a printed circuit board assembly.
In general, most printed circuit board assemblies (PBAs) contain one or two heat generating sources that necessitate heat removal devices. In many cases a PBA is assembled with many low heat generating components such as capacitors, diodes and transistors. Although each device generates very little heat so that individually the heat can be ignored, the cumulative heat from the combined devices can be substantial. Furthermore, it is more difficult to extract heat from the scattered heat sources (devices) than it would be to extract heat from a single high heat source.
Generally, heat is usually extracted from a concentrated heat source by either heat sink or fan or both. Integrating fans into the PBA to remove heat has typically proven to produce a relatively unreliable PBA due to interference by the fan motor. Most heat producing devices are mounted directly to a heat sink, but only if there is room for the heat sink and if there are only one or two heat generating devices on the PBA. In most cases, PBAs are assembled with surface mount devices that require components to be soldered on the bottom of the printed circuit board assembly. This creates a mounting problem because of the potential short circuits between solder connections that could occur because of a metal mounting tray.
There is therefore a need in the art for providing a system and method that will transfer heat from heat producing devices that are scattered over a printed circuit board assembly. It would further be desirable to provide a system and method for passive heat transfer that did not interfere with individual devices on board the printed circuit board assembly.
To address the above-discussed deficiencies of the prior art, it is a primary object of the present invention to provide, a passive heat transfer system for use in a printed circuit board assembly.
It is a further object of the present invention to provide a system for transferring heat away from multiple, scattered components on a printed circuit board assembly.
It is still another object of the present invention to provide a system for transferring heat from multiple scattered components on the printed circuit board assembly and allow easy access for installation and service to the PCB.
The foregoing objects are achieved as is now described. A printed circuit board assembly mounting tray combined with a hinged thermal tray. The thermal tray, having a plurality of heat pipes and a thermal hinge, transfers heat gathered from heat sources scattered on the printed circuit board assembly and conducted to the mounting tray. The thermal hinge provides a heat transfer connection between the thermal tray and an external heat dissipation apparatus. Additionally, the thermal tray and thermal hinge combination provides easy inspection, board installation and serviceability.
The foregoing has outlined rather broadly the features and technical advantages of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.
Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms xe2x80x9cincludexe2x80x9d and xe2x80x9ccomprise,xe2x80x9d as well as derivatives thereof, mean inclusion without limitation; the term xe2x80x9cor,xe2x80x9d is inclusive, meaning and/or and the phrases xe2x80x9cassociated withxe2x80x9d and xe2x80x9cassociated therewith,xe2x80x9d as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.